Atherosclerosis, the clogging of arteries with plaque, is often a cause of coronary heart disease or vascular problems in other regions of the body. Plaque is made up of fat, cholesterol, calcium, and other substances found in the blood. Over time, the plaque hardens and narrows the arteries. This limits the flow of oxygen-rich blood to organs and other parts of the body.
Blood flow through the peripheral arteries (e.g., carotid, iliac, femoral, renal etc.), can be similarly affected by the development of atherosclerotic blockages. Peripheral artery disease (PAD) can be serious because without adequate blood flow, the kidneys, legs, arms, and feet may suffer irreversible damage. Left untreated, the tissue can die or harbor infection.
One method of removing or reducing such blockages in blood vessels is known as rotational atherectomy. In some implementations, a drive shaft carrying an abrasive burr or other abrasive surface (e.g., formed from diamond grit or diamond particles) rotates at a high speed within the vessel, and the clinician operator slowly advances the atherectomy device distally so that the abrasive burr scrapes against the occluding lesion and disintegrates it, reducing the occlusion and improving the blood flow through the vessel. Examples of some rotational atherectomy devices are depicted in U.S. Patent Publication Nos. 2009/0018564, 2009/0182359, 2009/0069829, 2009/0312777, 2009/0326568, 2009/0318942, 2010/0010522, 2010/0049226, 2011/0009888, 2012/0109170, and 2012/0035633; British Patent Publication No. GB2454943; and U.S. Pat. Nos. 4,990,134; 5,314,438; 6,132,444 and 6,146,395.